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diff --git a/man-pages-posix-2013/man1p/df.1p b/man-pages-posix-2013/man1p/df.1p new file mode 100644 index 0000000..ef1579d --- /dev/null +++ b/man-pages-posix-2013/man1p/df.1p @@ -0,0 +1,332 @@ +'\" et +.TH DF "1P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. + +.SH NAME +df +\(em report free disk space +.SH SYNOPSIS +.LP +.nf +df \fB[\fR\(mik\fB] [\fR\(miP|\(mit\fB] [\fIfile\fR...\fB]\fR +.fi +.SH DESCRIPTION +The +.IR df +utility shall write the amount of available space +and file slots +for file systems on which the invoking user has appropriate read +access. File systems shall be specified by the +.IR file +operands; when none are specified, information shall be written for all +file systems. The format of the default output from +.IR df +is unspecified, but all space figures are reported in 512-byte units, +unless the +.BR \(mik +option is specified. This output shall contain at least the file system +names, amount of available space on each of these file systems, +and, if no options other than +.BR \(mit +are specified, the number of free file slots, or +.IR inode s, +available; when +.BR \(mit +is specified, the output shall contain the total allocated space as well. +.SH OPTIONS +The +.IR df +utility shall conform to the Base Definitions volume of POSIX.1\(hy2008, +.IR "Section 12.2" ", " "Utility Syntax Guidelines". +.P +The following options shall be supported: +.IP "\fB\(mik\fP" 10 +Use 1\|024-byte units, instead of the default 512-byte units, when +writing space figures. +.IP "\fB\(miP\fP" 10 +Produce output in the format described in the STDOUT section. +.IP "\fB\(mit\fP" 10 +Include total allocated-space figures in the output. +.SH OPERANDS +The following operand shall be supported: +.IP "\fIfile\fR" 10 +A pathname of a file within the hierarchy of the desired file system. +If a file other than a FIFO, a regular file, a directory, +or a special file representing the device containing the file system +(for example, +.BR /dev/dsk/0s1 ) +is specified, the results are unspecified. If the +.IR file +operand names a file other than a special file containing a file +system, +.IR df +shall write the amount of free space in the file system containing the +specified +.IR file +operand. +Otherwise, +.IR df +shall write the amount of free space in that file system. +.SH STDIN +Not used. +.SH "INPUT FILES" +None. +.SH "ENVIRONMENT VARIABLES" +The following environment variables shall affect the execution of +.IR df : +.IP "\fILANG\fP" 10 +Provide a default value for the internationalization variables that are +unset or null. (See the Base Definitions volume of POSIX.1\(hy2008, +.IR "Section 8.2" ", " "Internationalization Variables" +for the precedence of internationalization variables used to determine +the values of locale categories.) +.IP "\fILC_ALL\fP" 10 +If set to a non-empty string value, override the values of all the +other internationalization variables. +.IP "\fILC_CTYPE\fP" 10 +Determine the locale for the interpretation of sequences of bytes of +text data as characters (for example, single-byte as opposed to +multi-byte characters in arguments). +.IP "\fILC_MESSAGES\fP" 10 +.br +Determine the locale that should be used to affect the format and +contents of diagnostic messages written to standard error and +informative messages written to standard output. +.IP "\fINLSPATH\fP" 10 +Determine the location of message catalogs for the processing of +.IR LC_MESSAGES . +.SH "ASYNCHRONOUS EVENTS" +Default. +.SH STDOUT +When both the +.BR \(mik +and +.BR \(miP +options are specified, the following header line shall be written (in +the POSIX locale): +.sp +.RS 4 +.nf +\fB +"Filesystem 1024-blocks Used Available Capacity Mounted on\en" +.fi \fR +.P +.RE +.P +When the +.BR \(miP +option is specified without the +.BR \(mik +option, the following header line shall be written (in the POSIX +locale): +.sp +.RS 4 +.nf +\fB +"Filesystem 512-blocks Used Available Capacity Mounted on\en" +.fi \fR +.P +.RE +.P +The implementation may adjust the spacing of the header line and the +individual data lines so that the information is presented in orderly +columns. +.P +The remaining output with +.BR \(miP +shall consist of one line of information for each specified +file system. These lines shall be formatted as follows: +.sp +.RS 4 +.nf +\fB +"%s %d %d %d %d%% %s\en", <\fIfile system name\fR>, <\fItotal space\fR>, + <\fIspace used\fR>, <\fIspace free\fR>, <\fIpercentage used\fR>, + <\fIfile system root\fR> +.fi \fR +.P +.RE +.P +In the following list, all quantities expressed in 512-byte units +(1\|024-byte when +.BR \(mik +is specified) shall be rounded up to the next higher unit. The fields +are: +.IP "<\fIfile\ system\ name\fP>" 10 +.br +The name of the file system, in an implementation-defined format. +.IP "<\fItotal\ space\fP>" 10 +The total size of the file system in 512-byte units. The exact meaning +of this figure is implementation-defined, but should include +<\fIspace\ used\fP>, <\fIspace\ free\fP>, plus any space reserved by +the system not normally available to a user. +.IP "<\fIspace\ used\fP>" 10 +The total amount of space allocated to existing files in the +file system, in 512-byte units. +.IP "<\fIspace\ free\fP>" 10 +The total amount of space available within the file system for the +creation of new files by unprivileged users, in 512-byte units. When +this figure is less than or equal to zero, it shall not be possible to +create any new files on the file system without first deleting others, +unless the process has appropriate privileges. The figure written may +be less than zero. +.IP "<\fIpercentage\ used\fP>" 10 +.br +The percentage of the normally available space that is currently +allocated to all files on the file system. This shall be calculated +using the fraction: +.RS 10 +.sp +.RS 4 +.nf +\fB +<\fIspace used\fR>/( <\fIspace used\fR>+ <\fIspace free\fR>) +.fi \fR +.P +.RE +.P +expressed as a percentage. This percentage may be greater than 100 if +<\fIspace\ free\fP> is less than zero. The percentage value shall be +expressed as a positive integer, with any fractional result causing it +to be rounded to the next highest integer. +.RE +.IP "<\fIfile\ system\ root\fP>" 10 +.br +The directory below which the file system hierarchy appears. +.P +The output format is unspecified when +.BR \(mit +is used. +.SH STDERR +The standard error shall be used only for diagnostic messages. +.SH "OUTPUT FILES" +None. +.SH "EXTENDED DESCRIPTION" +None. +.SH "EXIT STATUS" +The following exit values shall be returned: +.IP "\00" 6 +Successful completion. +.IP >0 6 +An error occurred. +.SH "CONSEQUENCES OF ERRORS" +Default. +.LP +.IR "The following sections are informative." +.SH "APPLICATION USAGE" +On most systems, the ``name of the file system, in an +implementation-defined format'' is the special file on which the +file system is mounted. +.P +On large file systems, the calculation specified for percentage used +can create huge rounding errors. +.SH EXAMPLES +.IP " 1." 4 +The following example writes portable information about the +.BR /usr +file system: +.RS 4 +.sp +.RS 4 +.nf +\fB +df \(miP /usr +.fi \fR +.P +.RE +.RE +.IP " 2." 4 +Assuming that +.BR /usr/src +is part of the +.BR /usr +file system, the following produces the same output as the previous +example: +.RS 4 +.sp +.RS 4 +.nf +\fB +df \(miP /usr/src +.fi \fR +.P +.RE +.RE +.SH RATIONALE +The behavior of +.IR df +with the +.BR \(miP +option is the default action of the 4.2 BSD +.IR df +utility. The uppercase +.BR \(miP +was selected to avoid collision with a known industry extension using +.BR \(mip . +.P +Historical +.IR df +implementations vary considerably in their default output. It was +therefore necessary to describe the default output in a loose manner to +accommodate all known historical implementations and to add a portable +option (\c +.BR \(miP ) +to provide information in a portable format. +.P +The use of 512-byte units is historical practice and maintains +compatibility with +.IR ls +and other utilities in this volume of POSIX.1\(hy2008. This does not mandate that the +file system itself be based on 512-byte blocks. The +.BR \(mik +option was added as a compromise measure. It was agreed by the standard +developers that 512 bytes was the best default unit because of its +complete historical consistency on System V (\fIversus\fP the mixed +512/1\|024-byte usage on BSD systems), and that a +.BR \(mik +option to switch to 1\|024-byte units was a good compromise. Users who +prefer the more logical 1\|024-byte quantity can easily alias +.IR df +to +.IR df +.BR \(mik +without breaking many historical scripts relying on the 512-byte +units. +.P +It was suggested that +.IR df +and the various related utilities be modified to access a +.IR BLOCKSIZE +environment variable to achieve consistency and user acceptance. Since +this is not historical practice on any system, it is left as a possible +area for system extensions and will be re-evaluated in a future version +if it is widely implemented. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIfind\fR\^" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "Chapter 8" ", " "Environment Variables", +.IR "Section 12.2" ", " "Utility Syntax Guidelines" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.unix.org/online.html . + +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |